Milo Ventimiglia, Mandy Moore, and the "This Is Us" team also confirmed casting for Jack's brother while Sterling K. Brown got pranked by his castmate.

“You can do whatever you want in those shoes, man,” Chris Sullivan told Sterling K. Brown on stage Monday night — and Brown did just that.

Taking part in an FYC panel for “This Is Us” — and kicking off Day 1 of voting for the 2018 Emmy winners — Brown did it all. He sat and listened attentively to his co-stars, including Sullivan, Ventimiglia, Moore, Chrissy Metz, Justin Hartley, and Susan Kelechi Watson. He provided long, thoughtful answers to any questions tossed his way. He helped out when the microphones malfunctioned. He even gave Sullivan a hug mid-panel… after Sullivan tricked him into freestyle rapping in front of TV Academy members considering whether or not to give Brown his third Emmy.

After moderator Nellie Andreeva, Deadline’s co-editor-in-chief for TV, said she was told Brown is a skilled “freestyle rapper,” Sullivan said “I heard that, too!” Before Brown could respond, Susan Kelechi Watson started beatboxing, and it was on:

Yeah I can do a little something here up on the stage
I’m young Randall playing my own age
I don’t know where this information came from
But I can definitely give you a little somethin’ somethin’

The crowd cheered, but Brown immediately apologized for his impromptu attempt because he didn’t know what he was doing.

The night’s oddities didn’t end there. Though the panel was bookended by hard news — “I’m Dying Up Here’s” Michael Angarano will play Jack’s brother Nicky, while the audience got an exclusive look at a Season 3 episode featuring Jack (Ventimiglia) and Rebecca’s (Moore) first date — what voters may remember most (beyond Brown’s charm) is a pitch for Dan Fogelman’s upcoming film, “Life Itself.”

After noting that “This Is Us” Season 3 is set to premiere September 25, just four days after the creator’s new movie hits theaters on September 21, the cast launched into a passionate campaign for the film starring Oscar Isaac, Olivia Wilde, Annette Bening, Mandy Patinkin, and more.

“It’s one of the best movies I’ve ever seen in my life,” Ventimiglia said, adding, “It’s phenomenal,” and “It leaves you full. It’s such a beautiful, beautiful story.”

“That movie is so good,” Watson said. “You may lose your life [from crying], is what I’m trying to say. It’s like ‘Memphis’ and ‘The Fire’ as one episode.”

“There’s like a Spanish Jack and Rebecca. Seriously, you’ll see,” Brown said. “This is what I like about Dan; he’s never content to rest on his laurels and the next thing he does, he wants to be the best thing he does.”

“Go see this movie,” Sullivan said. “My wife and I saw a screening, and the way ‘This Is Us’ zooms way in on people and gets minute with them, this movie zooms out on life in a way that when my wife and I left the theater here on the lot, we were different people. We were moved — I mean, moved — from one place to another in our life.”

The cast was also enthused about the new season, including an episode dedicated to Sullivan’s Toby (and simply titled, “Toby”) as well as the Season 3 premiere (which Fogelman called “one of our best episodes [ever]”). Fogelman said a baby being born could be “a potential story” and confirmed Jack’s brother died during Vietnam — “But we don’t know how,” he added, nodding to a similar mystery surrounding Jack’s death prior to the tell-all “Super Bowl” episode.

But all that paled in comparison to their overt support of “Life Itself” and, of course, the man attached to Sterling K. Brown’s shoes.